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Firefox 91 HSTS

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I have multiple computers, all Win10, All use Firefox. Recently one computer the HD crashed. I reinstalled Win10, Firefox, and a couple of other MS programs, all used on the other computers. The other computers all updated to 91.0.1, The new install is also 91.0.1. If I try to go to Google.com on the newly installed computer I get: Did Not Connect: Potential Security Issue

Firefox detected a potential security threat and did not continue to www.google.com because this website requires a secure connection.

All the other computers search and go to Google just fine. So it is obvious it is something new between Google, Firefox and Win 10, the version of Win10 is 19042.1165 (win10 home) I have searched (using Edge and Bing) for some type of answer, but everything is from 2015/16 and older. Firefox when first installed, before the 91 update on Aug 20th, did work, it was after the Aug 20th update Google (and Bing) stopped with the security issue. I do not care for Edge or Bing, I hope someone can give me some ideas. Thankyou in advance.

I have multiple computers, all Win10, All use Firefox. Recently one computer the HD crashed. I reinstalled Win10, Firefox, and a couple of other MS programs, all used on the other computers. The other computers all updated to 91.0.1, The new install is also 91.0.1. If I try to go to Google.com on the newly installed computer I get: Did Not Connect: Potential Security Issue Firefox detected a potential security threat and did not continue to www.google.com because this website requires a secure connection. All the other computers search and go to Google just fine. So it is obvious it is something new between Google, Firefox and Win 10, the version of Win10 is 19042.1165 (win10 home) I have searched (using Edge and Bing) for some type of answer, but everything is from 2015/16 and older. Firefox when first installed, before the 91 update on Aug 20th, did work, it was after the Aug 20th update Google (and Bing) stopped with the security issue. I do not care for Edge or Bing, I hope someone can give me some ideas. Thankyou in advance.

Chosen solution

Google always comes with a certificate issued by "Google Trust Services LLC", so there is obviously something wrong in your case.

You can check the connection settings.

  • Settings -> General -> Network: Connection -> Settings

If you do not need to use a proxy to connect to internet then try to select "No Proxy" if "Use the system proxy settings" or one of the others do not work properly.

See "Firefox connection settings":

You can do a malware scan just to be sure.

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All Replies (6)

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There is security software like Avast, Kaspersky, BitDefender and ESET that intercept secure connection certificates and send their own.

https://support.mozilla.org/en-US/kb/firefox-cant-load-websites-other-browsers-can

https://support.mozilla.org/en-US/kb/firefox-and-other-browsers-cant-load-websites

https://support.mozilla.org/en-US/kb/secure-connection-failed-error-message

https://support.mozilla.org/en-US/kb/connection-untrusted-error-message

Websites don't load - troubleshoot and fix error messages

http://kb.mozillazine.org/Error_loading_websites

What do the security warning codes mean

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Went through the support articles. None of them seem to specifically apply. I also find it interesting on the troubled computer that Edge/Bing has no issues going the Google.com, Only Firefox has this issue, and the issue is trying to go to Google or Bing, there may be other websites, I don't know. The issue does also appear directly related to Firefox having an issue with a HSTS whatever, I don't know if it is Firefox reading it or what it is reading is wrong. Tried the Help troubleshooter, no change, same thing happens. Looking at the certificate for Google, nothing appears flagged, but then I have no idea what it should look like.

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You can compare the certificate as shown in the certificate viewer (Tools -> Page Info -> Security). Can you post the base64 encoded certificate data for Google ?

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Pics are from the Firefox page with the error, tools, page info, security, view certificate.

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Chosen Solution

Google always comes with a certificate issued by "Google Trust Services LLC", so there is obviously something wrong in your case.

You can check the connection settings.

  • Settings -> General -> Network: Connection -> Settings

If you do not need to use a proxy to connect to internet then try to select "No Proxy" if "Use the system proxy settings" or one of the others do not work properly.

See "Firefox connection settings":

You can do a malware scan just to be sure.

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OMG, How stupidly simple. I didn't even consider Firefox would setup a proxy, I never use a proxy. Thank you so very much, I didn't even check that, I made the assumption (gulp) it was what I always set it up as, and sure enough Proxy was turned on. doah.